From WordNet (r) 2.0 (August 2003) [wn]:
jejune
adj 1: lacking in nutritive value; "the jejune diets of the very
poor" [syn: insubstantial]
2: displaying or suggesting a lack of maturity; "adolescent
insecurity"; "jejune responses to our problems"; "their
behavior was juvenile"; "puerile jokes" [syn:
adolescent, juvenile, puerile]
3: lacking interest or significance; "an insipid personality";
"jejune novel" [syn: insipid]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Jejune \Je*june"\, a. [L. jejunus fasting, hungry, dry, barren,
scanty; of unknown origin.]
[1913 Webster]
1. Lacking matter; empty; void of substance.
[1913 Webster]
2. Void of interest; barren; meager; dry; as, a jejune
narrative.
3. Juvenile; childish; immature.
[PJC]
4. Lacking nutritional value.
[PJC] - Je*june"ly, adv. -- Je*june"ness, n. --Bacon.
[1913 Webster]